To accelerate electrons to form a cathode ray beam in a vacuum tube, a high potential difference is required between the cathode and the anode. Which of the following electrical supplies is most suitable for this purpose?
12 V a.c.12\text{ V a.c.}12 V a.c.
12 V d.c.12\text{ V d.c.}12 V d.c.
3 kV a.c.3\text{ kV a.c.}3 kV a.c.
3 kV d.c.3\text{ kV d.c.}3 kV d.c.
55 exam-style questions on CIE IGCSE Physics 4.2.3a Electromotive force. Each one has a worked solution and a mark scheme showing where the marks go.